Purine Metabolism. Ii. the Effect of the Ingestion of Glycine on the Excretion

It has been generally accepted that the ingestion of high protein diets leads to an increased excretion of endogenous uric acid. In his review on purine metabolism, Rose (1) has summarized the important contributions on this phase of the subject and has also discussed the various theories which have been formulated to explain the observed phenomena. Lewis, Dunn, and Doisy (2) have made a careful study of the hourly elimination of uric acid by fasting individuals following the ingestion of proteins and amino acids. Definite increases in uric acid excretion were observed in all cases with a maximum effect 3 to 4 hours after the ingestion of protein and 2 to 3 hours after the ingestion of amino acids. The increased uric acid elimination was considered by these authors to be due to an increased production of uric acid, as a result of the stimulating action of the absorbed amino acids. The authors have cited the specific dynamic action of proteins and protein derivatives as a parallel phenomenon. In the experiments just cited the hourly elimination of creatinine was practically constant. Zwarenstein (3) was of the opinion that if there was a general increase in cellular metabolism, there should also be an increase in creatinine elimination coincident with the increase in uric acid. Zwarenstein, therefore, repeated the work of Lewis, Dunn, and Doisy. His results indicated that the hourly excretion of uric acid by fasting individuals was not affected by the ingestion of proteins and amino acids. Inasmuch as these results are at variance with all preceding work since 1905, it was thought advisable to make a study of the ex-